The invention relates to direct drive systems for agricultural equipment and, more specifically, to a drive train for a baler for large round bale consisting of gearboxes and interconnecting shafts.
In recent years, the agricultural practice of collecting crop materials, such as corn stalks, straw, green forage crops, and grasses, has been revolutionized by baling machines which produce large round bales of up to approximately six feet in diameter. Examples of such baling machines are described in U.S. Pat. Nos. 3,722,197 and 4,172,354. Such machines include two, opposite and spaced apart side walls that support a plurality of transverse shafts or rollers extended therebetween. A plurality of endless belts are trained about the shafts and define a baling chamber in which the large round bale is formed. A crop pick-up mechanism picks up crop material off the ground and feeds it into the baling chamber where the plurality of endless belts roll and compress the crop material into a large round bale.
Most such baling mechanisms are driven from the power takeoff of a tractor which is used to pull the baling machine over the ground. A main drive sprocket located on the outside of one of the side walls is interconnected to the tractor power take-off typically by a 90-degree gearbox. A plurality of roller chains are used to transmit rotation of the main drive sprocket to certain of the transverse shafts for driving the shafts and thereby the plurality of endless belts. A roller chain also is used to transmit rotation of the main drive sprocket to a drive mechanism for the crop pick up means.
The roller chains and sprocket drive mechanism suffers from a number of draw backs and limitations. The chains must be constantly lubricated by a brush and drip system or the like. Although the chains are typically housed behind a shield, the baling operation gives rise to large amounts of chaff and other finely divided crop material that finds its way inside the housing and collects on the oiled chains and sprockets. Roller chains also stretch as a result of use and so to maintain the required tension require either the use of a spring-loaded idler or the like or periodic adjustment. Further, the endless chains carry a substantial load during operation and can, if improperly maintained, break and cause bodily injury to an operator.